Urgent help please

[Arlo]

Hello

I really need some help and advice

I had 2 male gerbils that I rescued and unfortunately 2 weeks ago one had a major stroke and I had to have him put down
I never knew their exact age but it’s around 1.5 years
My boy that was left behind I did research and decided on getting 2 male pups to introduce
I waited 2 weeks and then the transition was smooth and they seemed to be getting on great

However today after 4 days together I noticed muffy was mounting the babies and chasing them around (one in particular) and I suddenly panicked that the male gerbils I had been sold were perhaps females

I took the babies out and tried to determine their sex but I have no knowledge of this and I’m 50/50
I rang the pet shop who were completely unhelpful but said to bring them in tomorrow

I made the painstaking decision to take muffy out as he was constantly trying to mount for many hours without relent and I felt that was best until I’m sure - however now I’m in such a dilemma that potentially now 2 young (approx 12-15 week) gerbils are pregnant and now muffy alone again

I know I need confirmation tomorrow but any help or advice in the meantime would be greatly appreciated

[gerbilord]

It could just be a dominance thing, the older gerbil making sure the younger ones know who's in charge.
You should be able to find a thread on this forum about sexing gerbils.
the best way to tell if the gerbil is male or female is to gently lift up the tail and see where the anus and the urinary organ are. On males they are further apart. Here is a link to a page about sexing gerbils:
www.thegerbils.com/breeding2sex.htm
If it is possible, please send pictures of the gerbils, with their tails lifted, on the forum so their sex can be guessed